This invention relates generally to the field of manufacturing. In particular, the present invention relates to the preparation of metallic alloy powder used to create either hot isostatically pressed or extruded metallic alloy logs that are subsequently converted through additional thermomechanical processing and machining into aerospace products, but this invention is also applicable to any product that employ powder constituents as raw material anywhere during its manufacturing process (for example pharmaceuticals, pigment, electronics, catalysts, and others).
In preparation for manufacturing, a powder, composed of the particles of a given and rather broad distribution, is introduced through an opening at the top of a can. It falls through an atmosphere in the can, and as it free falls it creates a pyramid shaped cone at the bottom of the can. During the free-fall the powder particles segregate due to the size differentiation (as defined by kinetics-of-flow). The segregation further progresses during the formation of the cone, the coarse particles may be free-flowing while the finer particles can be cohesive with a tendency to accumulate in the center of the cone. In addition, very fine particles are suspended in the can atmosphere and due to the electrostatic attraction to the can walls will with time adhere to the can walls. However, the very fine particles may detach from the walls and fall to the bottom of the can in clumps to further segregate the powder in the cone.
This segregation leads to non-homogeneity in a final manufacturing product due to the variability in microstructure and properties of the powder. This non-homogeneity may ultimately result in a final manufacturing product not matching the desired specification. Non-homogeneity of final product is typically undesirable in the final product of metallic alloy powders.